This invention relates to a method and apparatus for drying fabrics such as textiles.
Large commercial dryers are used for drying fabrics in a variety of applications. For example, such dryers are used by commercial laundries, towel services, diaper services, and textile manufacturers and processors.
Much attention has been directed to improving the performance of such dryers. For example, U.S. Pat. Nos. 1,564,566; 3,157,391; 3,861,865; 3,882,613; 3,419,969; 3,601,903; 3,815,257; 3,831,294; 3,921,308; 3,995,998; and 4,010,550, and U.S. patent application Ser. No. 42,134 filed May 24, 1979, now U.S. Pat. No. 4,268,247, all relate to improvements in dryers and/or drying of textiles. All of these patents and the patent application are incorporated herein by this reference.
Commercially available dryers are able to quickly dry large quantities of fabrics. In a typical drying cycle, hot air is introduced into a tumbled drying chamber for about 15 minutes to dry the fabrics, and then the drying chamber is cooled for an additional 5 minutes by introducing ambient temperature air. The air for drying is heated by either direct heating or indirect heating. Direct heating involves directly combining the air that is to be introduced into the drying chamber with hot gaseous combustion products of a fuel such as natural gas or fuel oil. With indirect heating, the air to be introduced into the drying chamber is heated with a heat-exchange apparatus which can contain as a working fluid steam, or the air is heated with electric heaters.
Regardless of the method used for heating the air, drying usually requires burning of a fossil fuel. Due to recent escalations in the price of fossil fuels, drying fabrics has become very expensive. Therefore, attention has been directed to methods for increasing the efficiency of dryers. In addition, attention has been directed to methods for reducing the length of the drying cycle. More efficient utilization of equipment and labor could be obtained if the time required for drying a batch of fabrics could be reduced.
Therefore, it is apparent that there is a need for a method and apparatus for drying fabrics that reduces the fuel cost for drying, and also reduces the length of the drying cycle.